1. Field of the Invention
The present invention relates to apparatus and methods for inspection or review of substrates, such as, for example, semiconductor wafers and masks.
2. Description of the Background Art
Emission electron microscopes include low energy emission microscopes (LEEM), photo-electron emission microscopes (PEEM), and secondary electron emission microscopes (SEEM). LEEM imaging systems detect electrons reflecting or mirroring off of the surface of a flat substrate. PEEM imaging systems detect photoelectrons emitted from a surface of a substrate. SEEM imaging systems detect secondary electrons emitted from a surface of a substrate
It is desirable to improve emission electron microscope systems, including those utilized for the automated inspection or review of substrate surfaces. More particularly, it is desirable to improve pixel alignment and image resolution in emission electron microscope systems.